2. Not a wise plan, talk to your company's immigration LAWYER and not some non-attorney in HR
3. Perhaps, talk to your company's immigration attorney.
PROFESSOR OF IMMIGRATION LAW for over 10 years -- This blog posting is offered for informational purposes only. It does not constitute an attorney-client relationship. Also, keep in mind that this is an INTERNET BLOG. You should not rely on anything you read here to make decisions which impact on your life. Meet with an attorney, via Skype, or in person, to obtain competent personal and professional guidance.
An example best serves your question. If the H1B petition is selected, it will have an effective validity date no earlier than October 01, 2014, assuming that it is subject to the visa cap. Thus, hypothetically if your husband's H1B petition is selected within the visa cap with an employment start date of Oct. 01, and he maintains L1 and you maintain L2 status until Oct. 01, then your application to change status to H4 can be filed anytime prior to Oct. 01 (if your H1B petition is not selected within the visa cap).
The strategy of filing H1B/H4 at the same time and then withdrawing the H4 is too convoluted and can lead to problems.
You sound like a very valuable asset which American company B chose to sponsor, therefore, kindly direct all your immigration collateral issues to its attentive immigration counsel for clarifying your important objectives for you.
DISCLAIMER The answer given above by the lawyer serves for educational purposes only and provides general information and a basic understanding of the applicable law. Take notice that the answer above does not create an attorney-client relationship as this website is not intended to provide anyone a specific legal advice. Anyone using the site expressly consents that there is no attorney client privilege between any person and any attorney responding. Further take notice that the site should not be used as a crude substitute for any professional and competent legal advice by a licensed professional attorney in the applicable jurisdiction. The attorney above attempted to provide competent professional opinion, however, the law and its applications may change frequently and vary greatly from other U.S. jurisdictions and locales. Therefore, any information and opinions stated above are general in nature, and may not apply to specific factual or legal circumstances related to one's current legal issues. Contact an experienced lawyer admitted to practice in your State under an attorney-client privilege to further receive a comprehensive legal before making an educated decision about your particular legal issue. Respectfully, Attorney Alexander Ivakhnenko, Chicago, Illinois